In spirit. See 1:10; 17:3. “The precise implication of the words…escape us today. What the author presently describes, we readily call a vision; but the nature of ecstasy-if indeed this word should be used in preference to a more general term for supernatural phenomenon-and the modality of its communications are matters fully intelligible only to mystics” (Father Willian G. Heidt, O.S.B., The Book Of The Apocalypse, New Testament Reading Guide, vol 14, pgs 17-18).

To a great and high mountain: and he shewed me the holy city Jerusalem. Recalls the introduction to Ezekiel’s vision in chapter 40:1-2. For the full Ezekiel background see 40:1-47:12; 48:30-35.

The holy city of Jerusalem. Not the historical city, which St John has termed Sodom and Egypt in 11:8. This is the Church glorified.

Coming down out of heaven. The heavenly city coming down upon the mountain forms a contrast with Babylon which sits upon the waters (Rev 17:1), and with whom the kings of the earth fornicated (17:2).

Rev 21:11 Having the glory of God, and the light thereof was like to a precious stone, as to the jasper stone even as crystal.

The glory of God, is the Shekinah which Ezekiel saw leave the Temple and city of Jerusalem before the destruction wrought by Babylon (Ezek 10:18-23). The prophet saw its return in 43:4-5. But something greater than the rebuilt Jerusalem of the post Babylonian Exile is being described here; the city now has God as its temple (vss 22-23).

Jasper stone. God, the one on the throne, appeared like Jasper in 4:2-3. This connection with the throne vision indicates that God reigns in the city. The city reflects the glory of God and his divine radiance (light).

Rev 21:12 And it had a wall great and high, having twelve gates, and in the gates twelve angels, and names written thereon, which are the names of the twelve tribes of the children of Israel.
Rev 21:13 On the east, three gates: and on the north, three gates: and on the south, three gates: and on the west, three gates.
Rev 21:14 And the wall of the city had twelve foundations: And in them, the twelve names of the twelve apostles of the Lamb.

Twelve tribes…Twelve apostles of the Lamb. Establishes continuity between the people of God in the old and new dispensations (Testaments, Covenants). Notice however that the Apostles form the foundation of the city walls, whereas the twelve tribes of Israel are related to gates in those walls founded upon the Apostles. The fulfillment is far more important than the foreshadowing. The idea being symbolized here is similar to what is said in Hebrews 11. In this chapter the faith of the ancients is celebrated, but the author goes on to write: 39 And all these (i.e., the OT faithful), though well attested by their faith, did not receive what was promised, 40 since God had foreseen something better for us (NT faithful), that apart from us they should not be made perfect (RSV).

East…North…South…West…three gates. The city, with three gates on each of its four sides is being portrayed as symmetrical, and, therefore, perfect. Verse 15-17, not part of our reading, build upon this, describing the city as a cube, recalling the cube shape of the Holy of Holies (see 1 Kings 6:20; 2 Chron 3:8ff.), indicating that the city is now the place of God’s presence.

Rev 21:22 And I saw no temple therein. For the Lord God Almighty is the temple thereof, and the Lamb.

“As we have seen, the heavenly Jerusalem is described as one giant holy of holies. Now we realize why all in the heavenly city dwell in the presence of the Lord-He is the Temple. The righteous dwell within the Lord God and the Lamb. In other words, they are taken into the inner life of God; they live in the Trinity” (Michael Barber, Coming Soon, pg 265. See Resource List above).

Rev 21:23 And the city hath no need of the sun, nor of the moon, to shine in it. For the glory of God hath enlightened it: and the Lamb is the lamp thereof.

Much of verses 23-27 recall Isaiah 60. See also Isa 24:23; John 8:12; 1 John 1:5.

The repeated references to luminaries, (sun, moon) and light, recalls and provides contrasts with the lament over Babylon: “No light from a lamp will ever be seen in you again” (18:23 NAB).